Within Reason - #121 John Cottingham - The Father of Modern Philosophy: René Descartes

Episode Date: September 16, 2025

John Cottingham (born 1943) is an English philosopher. The focus of his research has been early-modern philosophy (especially Descartes), the philosophy of religion and moral philosophy. He is a Professor Emeritus of Philosophy at the University of Reading, Professorial Research Fellow at Heythrop College, University of London, and Honorary Fellow of St John's College, Oxford. He is also a current Visiting Professor to the Philosophy Department at King's College, London. Learn more about your ad choices. Visit megaphone.fm/adchoices

When you're with Amex Platinum, you get access to exclusive dining experiences and an annual travel credit. So the best tapas in town might be in a new town altogether. That's the powerful backing of Amex. Terms and conditions apply. Learn more at Amex.ca. John Cottingham, welcome to the show. Nice to be here.

Who was Rene Descartes? Well, Descartes is often described as an early modern philosopher. He wrote in the 17th century, and he was born in France in what's now called Descartes, which is somewhat odd. He said Descartes was born in Descartes, but in the Turin district. He went to school at La Flesch, at the Jesuit College, which he later described as one of the best in Europe. But most of his life, he was in Holland, where he wrote his great masterpieces. The best known works are the discourse on the method, written in French, published anonymously in 1637.

And then his, I think, his masterpiece, the meditations. the meditations on first philosophy, that's to say, metaphysics, which were published in Latin in 1641. But as well as being a philosopher in the modern technical sense to do with theory of knowledge, metaphysics and so on, he was also what we now call a scientist. He was a great mathematician, and he published a massive compendium of his scientific, views, which was called the Principia Philosophia, written in Latin, four parts in 1644. Towards the end of his life, he died quite young, he wrote another very important work, I think,

the passions of the soul, which is about the human being and the emotions and the feelings. So his, I think he's important, well, what attracted me to him was that his philosophy spans so many areas. It's, in my own work, I've argued for a synoptic conception of philosophy that instead of just focusing on narrow issues, takes in a broad range and sees how different parts of our worldview connect together or clash. And with Descartes, you've got metaphysics, you've got physics, he was interested in medicine and physiology, and in ethics, the questions about the good life. And as I mentioned, about the passions of the soul, that's to say, the psychology of the human being and the emotions. So we get an entire system, but he's also, you ask why he's important, he's also, he's also, a pivotal figure, I think, because he both looks back to the Middle Ages, and he was very influenced by the Christian scholastic philosophy of Thomas Aquinas, which he knew very well.

He doesn't acknowledge it in his writings, but in all sorts of places you can see the influence of that great medieval tradition, which is now, we know, scholasticism, kind of fusion of the Bible and Aristotle, really. Yeah, right. He defined himself in a way in opposition to that, to the Aristotelian approach, and claimed to be offering a new philosophical system. So that's important, too, because he envisaged a new kind of science based on mathematics, quantities, essentially, rather than the forms and qualities of the qualities of the old.

Aristotelian School of Philosophy. Yeah, well, he's often described as, like, the founding father of, like, Western philosophy. Do you think that's accurate? Where does that come from? I think, well, it's often said that he made questions of knowledge, the first questions in philosophy. There's some truth in that. And as I'm sure we'll be talking about, his famous cogito.

ergo sum, I'm thinking, therefore I exist, arises out of a process of seeing what can be doubted. He pushes doubt to its limits, arrives at an indubitable awareness of his own existence. So the questions about knowledge are the ones he starts with. But he very quickly moves on to questions which are still, I think, of interest. Questions about God, the existence of God, the foundations of knowledge, whether the existence of God somehow secures reliable knowledge, and perhaps most famously nowadays, the mind-body question, the nature of the mind and its relation to the body. Yeah, so Descartes's a little bit all over the place. Like you say, he's probably most famous today, remembered for this famous question.

quote, this cogito ergo sum, or as it first shows up, je pan stanchisei, I think therefore I am. Having said that, you've just translated it as I am thinking, therefore I exist, rather than I think therefore I am. There's maybe something to unpack there, but maybe we can start with sort of how we get there, because this is, as you say, like the foundation, the basis of the worldview, which he goes on to build up in the meditations. And the meditations begin with a kind of skepticism. Descartes realizes that there are so many things he believes about the world. He believes in the existence of the external world, this microphone in front of me,

but realizes that maybe that doesn't exist. You know, maybe I'm wrong about this. Maybe I'm wrong about that. And so he decides to start taking everything that it's possible to doubt, that we could think, well, I don't know if that's true. And let's treat it as though it's false and see what we're left with. So Descartes is often associated with this tradition of skepticism. Skeptics are people who think, are we, you know, we can't know anything, we don't know if the world exists.

And because of this process, Descartes is often called a skeptic, but that's probably not an accurate description of what Descartes doing. I agree with you. I think that's quite inaccurate and wrong. He uses doubt, but as a means to an end. Yeah. So the employment of doubt, which comes in three waves, really, leaves us with asking the question, does anything survive these three waves of doubt? So it's only a process with a definite goal in mind. The three waves just briefly are, first, the senses, most of our knowledge comes by the senses, but the senses, he says, are unreliable. Why? Well, well, He doesn't give many instances in the meditations, but there's some stock arguments he discussed with correspondence. For example, a stick in water may look bent, but really it's straight when you lift it out. So the senses give us confusing contradictory information, or they may seem

to. That's a worry that goes right back to Plato, so it wasn't original to Descartes. The second wave of doubt is the so-called dreaming argument. And here we are sitting. in London talking, but particularly if like Descartes, you're a vivid dreamer, particularly if you're a lucid dreamer, that's to say someone who even in the dreams wonders, oh, this is weird, perhaps it's a dream. And some people don't know what this,

they don't know what that is talking about, but many people have had that experience. For such people, it's eminently plausible that I might, might now wake up, and I'm not in London at all. I'm back home in bed. And that's exactly the doubt that Descartes. So I can't even be sure that I'm now sitting in this chair talking to you. But then he broadens it out and suggests that even chairs' tables may be dream-like illusions. As he says in the first meditation, the earth, the sky and all external

things may be the illusions of dreams. So there he's raising a question about whether I can be sure there really is a world, a planet Earth, objects around me. And then finally he introduces this scenario of the malicious demon. Yes. Who's employing all his energies to trick him with any illusions possible. So the whole shabang, the whole thing might be. But if he is being deceived, he must

exist. St. Augustine, many centuries earlier, had said, Cifalor sum, if I am being deceived, I must exist. And in a way, Descartes trades on that. Even if this demon

is deceiving, and there must be a me to be being deceived. And to pick up the point you raised, what he comes out with is, I think, I am thinking, therefore I exist. In other words, it's not I think. It's not a sort of general claim about me that from time to time I think. It's rather, at this moment, I'm thinking. Even if I'm doubting, I must be thinking, because doubting is itself a thought process. So as long as I'm thinking, I must exist.

There's nothing necessary about my thinking. I could stop any moment. I could cease to exist any moment. So there's nothing necessary about my existence. But so long as I, this is a very limited flickering candle of certainty, so long as I've actually engaged now in this process of thinking, for that period I must be existing. And not even the most all-powerful demon or God or malicious.

God could make me not exist. Of course, he could stop me existing, but he couldn't make me not exist so long as I'm thinking. Yeah, because you could not, you could stop existing, but then you wouldn't be thinking. And so Descartes is suddenly struck with, as you say, these waves of doubt. He's like, well, how can I know any of these things? So, well, I can't know this, I can't know that. What can I know with certainty? Well, I can know that this chair exists. Well, maybe not because maybe there's this malicious demon who is like affecting my senses. And a modern rethinking of this is the simulation idea. Some people think that we're living in a simulation as a matter of fact. But just as a skeptical tool, you could say, well, can you prove that this

isn't all a computer simulation and that somebody is fooling us into prodding our brains? We're a brain in a bat somewhere and it's all simulated. I'm not saying that's true. We're not saying we think we live in a simulation, we're just saying, how can we know that we're not? Because what we want is knowledge and certainty. And Descartes says, well, we can't know that. So what can I know with certainty? Well, if I doubt everything I can, doubting is a form of thinking. And as long as I'm thinking, there is a thinking being that's doing some thinking, which is me. And so this shows up first in the discourse and in the method, right, as Jean-Ponts-Den-Ju-sui, I think, therefore I am, is how it's usually translated. But as you just indicated, a problem with this idea is that

It kind of sounds like an argument. It sounds like somebody saying, premise one, I think, therefore, conclusion, I exist. But it's probably best not thought of in those terms. Right. I think Descartes wasn't entirely consistent when he was asked about this. Yeah. In the meditation, in the second meditation, the formula is sum existo. I am, I exist is certain.

as often as it's put forward by me or conceived in the mind. Quote is proffertor velmente contributor. So there's no, I think, therefore, there. He's just saying straight out, I am, I exist, is certain. But then the thinking comes in, as long as it's put forward or conceived in the mind. And to be clear, he doesn't say that, you know, I exist so long as I'm thinking.

He says, I am certain that I exist so long as I exist, so long as I'm thinking. It's the certainty that thinking guarantees. That's true. And indeed indubitable certainty, because even doubting it would confirm it. There are not many propositions such that doubting them entails their truth. Yeah, right. As far as the point you raise, very interesting point about whether it's a sort of argument, he was once asked about the status of the cogitur, if you like to put it that way. The cogito is this phrase.

I'm thinking, therefore, I can... From the Latin version, cogito ergo sum. I'm thinking. And of course, cogito, you can translate the present tense in Latin or in French, your panse, in two ways. Either I think or I am thinking. English has that luxury. And I think we, for the reasons I've just been saying, I think we should go for the second, I am thinking. But he was asked about, is this really the first proposition you can know?

does it sort of come out of nothing? And he says, when I said it's the first proposition, I didn't mean to imply that you don't, in order to do it, as it were, need to know other things. You need to know, he said, what thought is, what existence is, and that in order to think one must exist. Right. For panse, he'll be, in French. so that leaves it slightly unclear actually as to whether it's just a kind of performance something we sort of do

and as long as we do it we know we're certainly we have certainty that's true or whether there's some kind of implied inference well of course you know you could say as we just have we could say well look as long as I'm thinking I must exist and even if I doubt doubting is a kind of thinking and so this is our foundational bit of knowledge

and somebody could come along and say how do you know that if you're doubting then you're thinking because it's a kind of thinking it's eminently logical and what's this logic thing that you're talking? Is that a more foundational thing as if to say that

you do actually have to have some assumptions you need to believe in the law of non-contradiction the laws of logic, all of this kind of shallel before you can get to the cogito. I think that's right you know, it sometimes seems as if he's starting completely from scratch, and that actually is the metaphor he uses. He talks about destroying everything, erasing everything, and starting right from the foundations. But actually, even in order to start meditating at all, to start thinking,

you've got to have access to concepts, to its meaning. And this has given rise to, to a modern criticism of Descartes, namely that language, you've got to have language to start thinking, and that already implies a public world. This was made famous by Wittgenstein, Ludwig Wittgenstein, the famous 20th century philosopher who pointed out the language has to have public rules. You can't just make a private language, as he says. Precisely, the so-called private language argument. So Descartes, even in sitting in his lonely room by the fire, his stove-heated room, sitting in his winter dressing gown, this is the scenario he describes in the first meditation, even then he must

be drawing on a whole public domain of concepts, of language, of rules of language, and therefore there's something a bit suspect about the idea of a private starting point to knowledge. Yes, which would mean that this cogito couldn't serve as the actual foundation of knowledge because you need to know certain things in order to get there. Is that something that Descart either in the meditations or in his correspondence afterwards, like, recognises and addresses in his time? I think he's attracted to the idea of this first person starting point. And so although he acknowledged that in order to do it, you've got to know what thought means, what existence means, and that in order to think one must exist. Nonetheless, there's something, and I think this remains true for many people today,

there's something appealing about the idea that I just start with my own reflection. In a way, philosophy starts this way. Here I am thinking, I can push doubt to the limits, but then what will follow from that? that my own subjectivity, my own subjective awareness of my own existence, seems to have some kind of special status. It may not be logically justifiable, but I think it has an appeal. But of course, I should add that although he starts with just the eye, he very quickly moves out because he immediately becomes aware that among his thoughts he has this thought of or idea of God, which he reasons that he couldn't have constructed from his own resources.

Yeah, well, this is where the sort of next step comes in because, of course, Descartes, remember, the project is, you know, we want to see if we can justify our knowledge. So let's doubt everything we can. And as we said, Descartes isn't a skeptic. he's not inviting you to say you can't know anything. He's saying, look, well, we want to say that we can know this chair exists. So how can we justify that? How can we get there?

So he strips it down to the basis. And he says, OK, I think therefore I am, or I'm thinking therefore I exist. So I know that I exist. And the criticism is sort of like, what now? You know you exist, but you don't know in what form. You don't know if you have a body. You don't know if the external world exists. And I think a lot of people either forget or don't realize that the very same logic that

Descartes has just used to establish possibly the most. famous phrase in the history of philosophy, he then immediately uses the same logic to establish the existence of God. Yes. How does he do that? Yes. It's crucial for him. Although, and just before I come onto that, just to pick up what you were saying about not being

a skeptic. His target is science. He's got this new system of mathematically based physics, which he wants to introduce to the world. So he's heading for knowledge all the way. He's not wanting to subvert that. On the contrary, he's wanting to set it up. But uniquely, he sets it up via God.

This is what makes his philosophy very unusual in a way. Because I think normally we'd think, well, science starts with observation, maybe with some mathematical reasoning, maybe with some theories which we test. But the idea that you go via metaphysics, via God, is by modern standards pretty odd. And also importantly, we should say that Descartes is an example of what's known as a school of philosophy called rationalism.

And typically in the history of Western philosophy, we distinguish between the empiricists and the rationalists. And empiricists, people like David Hume, think that knowledge comes from our observations. So we see things in the world, and that's where knowledge comes from. For the rationalists, like Descartes, knowledge comes from within ourselves. So, whereas an empiricist might look at the world and say, well, look at this chair, look at that tree, from which we might say, do we think God exists? Descartes being a rationalist starts internally. And so one of the interesting sort of facets of that is that rather than looking at the world

to prove God, he looks to God to prove the world. That's very well put, if I may say so. And he follows here again, St. Augustine, who talked about, in the interior human, there dwells the truth. we go inside. And Descartes goes inside to his own thoughts and finds certain innate ideas that he thinks did not come from outside.

One of them is the idea of the self, the idea of thought. But most importantly, this idea of a being of infinite perfection. So how does he get to there? Well, as I'm thinking I exist. what am I is the next question? What is this thinking thing? Well, I know at once that I'm imperfect, there are many things I don't know, many things I can't do. So knowledge of one's

own existence carries for Descartes an immediate sense of how we fall short. I think there's something profound here about our human self-awareness. We have great aspirations, but we're aware of ourselves as lacking. We can't do everything we would like. We can't know everything we would like. But, reasons Descartes, Descartes, I also, looking within, again, as you were saying, looking inside me, I have a sense of something that doesn't fall short, something that's free from imperfections. In fact, he reasons from the very fact of seeing myself, as imperfect, that implicitly suggests that I have an idea of something that's perfect. From my very failings, I can dimly at least reach the idea of a being without such failure.

Imperfection is defined in terms of perfection. It's the negation of perfection. Yes. As C.S. Lewis put it in a slightly different context later on. A man cannot call the line crooked unless he has some idea of. of a straight line. Precisely. And Descartes actually says that the idea of perfection is prior to the idea of imperfection. That still perhaps doesn't get us to God. It just gets us to an idea. But Descartes goes on to suggest this idea is actually beyond me. I could not have

created it. Because the content of the idea, and here I think is influenced by his mathematical studies, the idea of infinity is something I actually can't grasp, but I can, as it were, reach towards it. Yeah, Descartes has this helpful distinction between understanding and imagining, right? Like, in that you might think to yourself, well, I don't have this idea of the infinite inside me, because I can't imagine infinity. And Descartes says, okay, well, can you understand a 112-sided shape? Yeah, I can understand what that is.

I can do maths with it. I can tell you facts about a 112-sided shape. But can I imagine it? Can I like grasp what it would look like? It kind of no. Like it's too many sides. I can't. And so even though I can't imagine it, Descartes says,

I can still understand the concept and what it means. And infinity for him is a bit like this, or the perfection is a bit like this. You're right. There's certainly a distinction in imagining and understanding in Descartes. So I can, I can't imagine a thousand-sided figure, but I can understand what's meant by it, and I can, as you were saying, prove properties of it. With the infinite, it's actually even more than that, because I can't even understand it fully. I can't comprehend it.

Descartes said in a letter to one of, to his editor, actually, Mersenne, Mar-a-Marsen, I can't, God is like the mountain. which I can't comprehend, I can't put my arms round it, but I can perhaps reach towards it in my thought. And the infinite is like that. I can never reach it. If you give me a number, I can always add one and say, well, it's not that. I can, as it were, reach towards it. But I already am aware of something that exceeds my grasp.

And that's, again, part of the tradition he inherited from Augustine and Aquinas. Aquinas says Thomas Aquinas in the 13th century says that God cannot be fully comprehended by the finite human mind. Augustine, even earlier

at the close of the Roman Empire, says, see comprehendis nonest deos. If you comprehend him, he's not God. If you think you've comprehended it, it's not God, it's some idol of your own creation. So, in a way, this argument, although Descartes presented it as a logical argument in the third meditation we're now talking about, it's more, I think, like an encounter.

This is the view taken by the great French philosopher Manuel Levinas in the 20th century. It's a kind of encounter of the finite limited mind with something infinitely beyond it. which can't be fully grasped, but which we already know we fall short of. Now, interestingly, for daycare, because there might be some confusion here in thinking, like, well, if we've stripped away everything, we're in the process of doubting, I know that I exist, but, you know, not everybody has this idea of infinity. Not every, like, you know, a newborn baby doesn't know what infinity means and hasn't thought about God. So, you know, is this a problem for Descartes? Because Descartes needs to, in order to establish God's

existence, he needs to say that I find within myself this idea, but if we're trying to strip everything away, not everybody has that idea, right? That's true. Not everyone has it, if you like, as an occurrent idea, actually active in the mind. But Descartes maintain that nonetheless it's there in the treasure house of the mind. He used that metaphor. You referred to his rationalism earlier, and the rationalists tend to believe in innate ideas that the might has this stock of innate ideas. Are they present when the baby's still in the womb, pretty clearly not actually present? We're not born meditating on metaphysics or in mathematics.

But Descartes says, whenever we, nonetheless, the idea is still there, waiting as it were to be thought about. Be drawn out, as is the etymological route of education. Yes. It means to draw out. Yes. And it's not difficult to imagine. I mean, obviously a baby doesn't know how to do calculus,

but it's not difficult to imagine that all of the, like, mental machinery needed to do calculus is there in that brain. It just needs the input data to sort of draw it out to unlock it. Yeah, I mean, this again is quite an ancient idea in philosophy. In Plato, there's a dialogue called the Meno, where Meno interrogates a slave boy who doesn't know any geometry. but he manages to get him by careful step-by-step reasoning to see how to construct a square,

which is double the area of a given square. And he didn't, as it were, he didn't put the knowledge in. He drew it out. Yeah, by working on the innate. So I think Descartes would say, no, we don't necessarily, we could go through life, never thinking about these questions, about God, but should someone draw the, rather like a triangle. You may never have thought of an Isosceles triangle, but once I draw your attention to it, I could get you to see certain

properties about the angle soon. Yeah. I think this is important to realize is that like, as we move on through this, we're about to sort of talk about this argument whereby Descartes reasons from this idea of God that we have, this idea of perfection, let's say, unlimited being, we can prove that he exists and we'll talk about why but some people might say but you know what if i don't have this idea and i think the point is that well maybe you don't have that idea and if you don't have that idea then maybe you can't be certain that god exists but descart had that idea and as long as he has that idea he's thinking what can i be certain of yes well if i have this idea and i know it can't have come from me then i know that god must exist just like a triangle if somehow the

existence of triangles proved god then if you thought of a triangle you'd prove you'd prove God. Yes. Doesn't mean you have to think of a triangle. It just means that if you do, you know, we can do this reasoning. Precisely. I think that's absolutely right. And that brings out, I think, an important point about Descartes' procedure.

It's not like a sort of blackboard set of philosophical arguments in a classroom. It's a process you have to go through. Yes. And in the preface to the meditations, Descartes says, I'm not interested in people who aren't prepared to go along with me and do the meditating. Something you have how to actually do. And as you follow, and you have to, as it would do it for yourself, each individual has to follow this path, the path of meditation, as the title implies.

And in doing that, you will come to see certain truths. Yeah, I mean, it seems very sort of brainy, like philosophy. He's sat there in his robe and he's just thinking. thinking and it's sort of an intellectual enterprise, the kind of thing you could write down on Blackboard. But Descartes valued experience. I mean, for him, the meditation was a, as you say, a sort of journey that he went through. But also, I mean, you've written in sort of semi-biography of him that, like, when he joined the army, it seemed from some of his writings that one of the things he most enjoyed was that he got to travel. And he just, like, was seeking

experience of the world, and at least in his earlier life, seems to value travel and lived experience over sitting down and just reading books. So it seems like within Descartes there is this value of actually experiencing, going on a journey, thinking, like living out thought rather than just, as you say, writing it on a blackboard. Yeah. Now, I think that's quite true. And although he goes on this sort of military, adventure, really. In the course of that, those travels, he ends up in this stove-heated room in Bavaria in southern Germany. And that's where we think this first idea occurred to him of founding a whole new system of philosophy, a marvelous new system, which would be based on

the innate ideas, what he called the clear and distinct ideas. of mathematics. Okay, so, well, put us out of our misery here. Where's this God coming from? So we've got as far as saying that Descartes has thought to himself, okay, I exist, and I'm aware that I have this conception of perfection, even if just because I realize I'm imperfect. And I don't mean, like, morally or something like that.

I just mean that, like, there are things I don't know. There are things I can't do, which implies that I'm limited. But this idea of limitation and imperfection only makes sense in the context of knowing what perfection means. So we have this idea of perfection and this perfection of the infinite. We sort of know what that means, even if we can't quite grasp it.

Okay, to someone listening, what's that got to do with God? Well, God, of course, is traditionally defined in terms of perfections, omnipotence, omniscience, and indeed benevolence. So God is, as Descartes was later to put it in the fifth meditation,

the sum of all perfections. And if he's the sum of all perfection, supreme perfection, then he must, they call out reasons, exist. This is a slightly different argument, the so called ontological argument. But I think, and that raises questions of its own. But I think from the standpoint of the earlier meditation of the third meditation,

the point is that I couldn't have constructed this idea from my own resources, therefore it must correspond to something real. Now the question is, why couldn't he have come up with the idea of infinity for himself? Why isn't that something that could just be the invention of Descartes's own mind? I think it hinges, I mean, this is the crucial question which will distinguish those who can accept the argument from those who just don't find it convincing. And as often in philosophy, I think there's no definitive way.

to establish which position is right. But from Descartes' point of view, he's encountered this notion of infinity, which is beyond him. He's encountered something beyond, in a certain way, beyond his grasp. And therefore, it must be real because it can't have come from inside.

Yeah. So this is something which, in the modern era, looking back at Descartes, we try to sort of put into argumentative form, and it's broadly known as the trademark argument, right? And this so-called trademark argument called the trademark because there's this thing inside of Descartes, which is perfection, which seems to have the trademark of God.

It's got this sort of nature about it which shows that it's from somewhere else. You know, it's got this trademark of God within him. And it relies on something which also has come to be called the causal adequacy principle. Can you tell us what that is? Yes. Well, the trademark, just starting with that, he recognizes the idea of God like the mark of the craftsman stamped on his work. It's a bit like the Alfred Hitchcock movies. This is one of the other, you know, Alfred Hitchcock always put himself in his movie. Yes. He's the man at the bus stop or the man in the lounge of the hotel reading a newspaper.

That's his trademark. Exactly. It shows the origin of the film. It's an authentic Hitchcock film. So similarly, the thought is that God planted this idea of infinite perfection in the mind of the meditator to be, as it were, the trademark, the mark of the craftsman stamped on the work. Now, I don't know if you want me to go into the details of the formal presentation of the argument, but the idea is that, the there is very crudely there's nothing in the in the effect which was not present in the cause so if you have an effect then the cause must be somehow adequate to producing that effect so for example you know you if something causes something else to be hot that cause also has to be hot you know a cold thing can't cause something to be hot exactly and you know like they're probably all all

kinds of examples we can think of. But in order for an effect to get something from a cause, the cause must have that thing. Precisely. And Descartes uses himself the idea of heat. So your cup of coffee there has a certain amount of heat. It can't have got it from nowhere. So it must have got it from a kettle or an urn or a stove, which was at least as hot as the heat in the coffee in that cup, it's got to be as hot or more hot, roughly. Now, that applies to physical things and seems plausible, but Descartes's going to go on to say it also applies to the content of ideas. And this is something very tricky, which is highly controversial. But the thought is, it's not just going to apply to physical

object, it's going to apply. Here's an analogy. Supposing you find a five-year-old child who's drawn a very intricate diagram of a computer circuit or something of that nature. You can reason, well, with the mental age of five, he just, he or she just couldn't have produced that. So it must have got it from somewhere else. Perhaps from a diagram in a book, where did that come from. The content, the richness, the intricacy must have come from somewhere, answer from the author from someone who had in his mind at least as much intricacy as you see in the diagram or in the chart. So rather neatly, Descartes's saying, I mean, the idea being analogous to the diagram or the drawing, the content of the drawing has still, even though it's just a drawing, not a real

thing, it's got to have a cause. So similarly, even though your idea of perfection is just an idea in your mind, something's got to put it. Yeah, that's awesome. Okay, so because the child just draws a picture of the computer. Computer doesn't exist. It's literally just a cartoon. But even though it's only a representation of a thing, it still has to have a cause, which really has the complexity that's represented in that idea. Precisely. And just as we look at the child and think, okay, you're a child, there's no, you don't know what a computer is,

that must have come from somewhere else. Descartes looks at us and goes, you're just a, you're just a limited human. You've got this idea of perfection, that must have come from somewhere else. You can say, well, that's just an idea of perfection. Well, it's just a drawing of a computer. It must have come from real complexity.

And this idea of perfection must have come from real perfection too. So this is the, what, as I say, been called the causal adequacy principle that the cause must have like an adequate amount of the relevant stuff to bring about the effect. Yes. And that's going to apply not just to physical properties, but to intellectuals, too representative property. Yes. The property is represented in a drawing or a diagram or in this case in an idea. Yeah. So by, you're very, very felt that you're able to represent to yourself in some form, albeit in a rudimentary form, because we can

never fully represent the infinite. But the very fact that we have some grasp of that notion shows that there must be, well, we can reason that there must be a cause, which is adequate to the complexity of that idea. And if the complexity of the idea is perfection, then it must come from something perfect. And like you say, it's important to note with a lot of these kinds of arguments, that I think one response people come up with is often to say, okay, but why does that have to be God? And I think it's important to point out that someone like Descartes could say, okay, forget the word God. Let's not talk about God. Let's just now admit that we've established the existence of a perfect being. If you don't want to call that God, you don't have to, but

what we're establishing here is that there must exist this perfect being. Okay, now, you know, we want to sort of do an overview of Descartes here, but I think people will be screaming at the screens and they'll want to know like, okay, that sounds kind of sensible, but there are a few problems that jump out. And I suppose let me give you two, just because this is the third meditation, like we say, we've got to the point where Descartes has established that he exists. He now thinks that a perfect being exists, and then we're going to move on. But people are going to say, well, okay, two problems. Firstly, this causal adequacy principle. Is it really true that what's in the effect has to be in the cause? For example, what about emergent properties?

A cake is spongy, right? And all of the things that made that cake, the flour, you know, the eggs, the hands that move, like the motion, all of that. None of those things are spongy, and yet all of those causes produce this effect of sponginess. So if the causal adequacy principle is correct, there must be sponginess in the cause, but there's no sponginess in the cause. Likewise with temperature, we now know temperature is just the excitation of atoms. and yet an atom on its own vibrating is not hot. It's an emergent property. And so it seems like we do have these effects which are not present in their causes.

Yes, you're throwing back at me at the sponge cake example, which I think I... From your very own book. And of course, it would be very crude to think that any given property, P, must be present in that form in the causes of it. but I think we can reason that there must be if you take for example the conservation of the energy principle in physics there must be at least as much energy in the cause of a given energetic phenomenon as you find in the phenomena kind of got it from nowhere and physicists will accept that happily today like they might want to quibble with the terminology the stake art wouldn't have been thinking in terms of atomic physics right but there is a reworked conception of the same argument.

Yes. And I think the thought is that in some form, either literally or in a higher form, whatever you find in the effect will be present in the cause. But as I say, I think although this can be structured as a logical argument, demonstration,

and Descartes was always attracted by the clarity of geometry, where you have absolute rigid demonstration. You know, you have axioms, definitions, and then certain theorems follow. And he was asked to present this proof in geometrical form by some of his interlocutors. And he did.

But whether it really makes it more convincing, personally, I'm not sure. To my mind, the most convincing way of thinking of it is as a process, as the meditator going through this process of doubt finding his own imperfection and then encountering something which exceeds his imperfect mind. And it's that encounter which I think delivers the goods for Descartes, although he was adept at producing elaborate formal proofs.

But I think it delivers more persuasive. than just presenting it as a kind of quasi-deductive process. And that's so often the case with philosophy. I talk all the time about coming to sort of belief in God, for example. There are syllogisms and arguments, but most people, in their actual personal life, the way that they come to profound philosophical changes is through profound philosophical realizations which are not of the kind oh wow gosh that third premise really does follow from the second one it's more like an intuition or something hits you or the penny drops you know as they

say and and something about reflecting on this nature of perfection for day car it's like oh this comes from outside of me the light bulb goes on yeah and i think actually there are very few arguments in philosophy if any where you can start with self-evident premises that every rational person must to agree to, and then step by step, forced them to conclusion. If that was true, then all the great problems of philosophy about determinism, free will, gone, so could be settled. But it clearly isn't like that. There's an interesting question as to what Descartes project is here, because like you said earlier, most people associate him with epistemology, the philosophy of how you know things, right? Because it seems like he's not even necessarily trying to establish what is

true, but rather what you can be certain of, or at the very least what it's impossible to doubt, which might not quite be the same thing. I think it's true that the two are different, but I think the importance of God for him, and we haven't yet come on to this, is that once he has to his satisfaction established such a God, the perfections of God mean that God is not a deceiver. So the creator god of the Christian, Judeo-Christian tradition cannot be malicious, cannot be. Why not? Because malice, deception is a sign of weakness.

Why would you lie to someone because you're frightened or because you're, there's something you want which you can't get? And none of that can apply to a supremely perfect being. Yeah, God is sort of the anti-evil demon. Where Descartes imagines the evil demon is this epistemic. problem, which is if there might be this evil demon who's deceiving me and the table doesn't exist, the epistemic solution is God, who because he is good, cannot deceive. Yes. Importantly, it's not as clear as like, because God exists, I know that the table exists.

There's still a few more steps. No, but at least I can have a hope of achieving the truth. I think truth now does come in. Yes. Because, as Descartes put it in an interview to a young Dutchman, France Boorman, in 1648, a reliable mind was God's gift to me. So in creating me, this perfect being would not have given me mental equipment that's fundamentally flawed. Yeah.

Now, that doesn't mean I have a hot line to the truth. Obviously, we all make mistakes in logic and mathematics in science all the time. But in principle, when we focus on the clearest and simplest propositions of logic and mathematics, Descartes reasons, we can't be wrong. Because, and I think actually, well, that may sound a bit sort of weird and faith rather than philosophical reason. But actually, I think we couldn't be having this conversation now unless we felt that, to some extent, at least, our minds are configured in such a way that we can track the truth. Yeah, yeah, that's an important argument that comes up in other contexts,

like the argument from reason and our ability to trust reason. I want to ask a question about that, but just beforehand, I wanted to give our listeners a taste of this, the way you talk about Descartes going on a journey and having sort of an experience. I think this is embodied in the second meditation, where in the first meditation, Descartes realizes all of these doubts. It thinks about the evil demon and all of this kind of stuff. And he opens the second meditation in this state of doubt.

And it's so interesting that in a philosophical text, you can read a sentence like this. He says, so serious are the doubts into which I've been thrown as a result of yesterday's meditation, that I can neither put them out of my mind nor see any way of resolving them. It feels as if I've fallen unexpectedly into a deep whirlpool, which tumbles me around so that I can neither stand on the bottom nor swim up to the top. And then he says, nevertheless, I will make it. effort and once more attempt to the same path I sat on yesterday. So he literally describes, again, this is like a foundational philosophical text.

It's not premise one, premise, two conclusion. He's saying, I've thought about this and I feel like I'm at a complete loss. I feel like I'm in a whirlpool. My feet can't find the ground. It's clearly like a deeply experiential thing for Descart. I think that's very important. And I think, although, as you know, I'm trained in the analytic tradition. I have great admiration for the methods of precision and clarity that is so important in Anglophone analytic philosophy.

Nonetheless, I think we often ignore that dimension, the dimension of the experiential. And if I can just quote another passage which is, I think, similar to that, this is at the end of the third meditation where he says, before examining all this more carefully, I should like to pause for a while and spend some time in the contemplation of God to reflect on his attributes and gaze with wonder and adoration at the beauty of this immense light. So that is not Descartes, the analytic reasoner doubting. That is a kind of submissive contemplation of the immense light of truth and goodness, which he thinks he's discovered. So, yes, we start in the world pool, we're absolutely lost, tumbled around. We

end up at a moment of calm contemplation. And these are both intensely personal, and I think intensely emotional experiences. Those words, you know, in the original text, it's almost like a litany, adore, admire, wonder at. And wonder, of course, is an emotion. Yeah, I mean, it's crucial and interesting to think that that exists at the foundation of this Western philosophical thought tradition. And yet it is still worth remembering that this is a philosophical text that people analyze as making a contribution to knowledge. And one important thing that we just sort of mentioned is this idea that Descartes establishing of God's existence is in part part of his epistemological project. to ground knowledge. In fact, Blaise Pascal and the Ponce says,

I will never forgive Descartes because Descartes sort of establishes God's existence to get his epistemology off the ground and then just has no need for him ever again. She's like, all right, thanks. See you later. I'm not sure if that's actually true in Descartes' personal life,

but that's what Pascal thought. The question that will spring to mind for people is, okay, let's just grant for a moment that Descartes has established with the light of reason that a perfect God exists. you've already indicated that this somehow gives us hope that God won't be a deceiver so the evil demon doesn't exist. But as you say, our minds still go wrong every now and again. You know, we do things incorrectly.

So how can Descartes use this as a way to justify our apprehension of truth if it's still the case that even though God exists, we still go wrong? Right. Yes, the problem of error. You know, in theology, there's the problem of evil. good God, how come all the suffering? In Descartes, we have a sort of epistemological analog of that, the problem of error. If God is the source of all truth, this perfect being, how come we go wrong? And Descartes' answer briefly is that, of course, we do go wrong, but we can't go wrong in the very simple and clear propositions. So as long as I am thinking I must exist, I couldn't be wrong

about that. Similarly, and he ranks this almost equally with the cogito, two plus three equals five. Now, of course, the malicious demon could muck about with the symbols, but as long as you and I are actually focusing on that proposition, as long as we're there attending to it, it can't be wrong. And Descartes has this crucial term of the clear and distinct perception. which he uses to delineate these particular kinds of perceptions. And for Descartes, perceptions are like, you know, the things that are in the mind, ideas and stuff like that. The apprehensions of the intellect.

So they're clear insofar as they're present, directly present to the mind. They're distinct insofar as they contain nothing except what is clear. And this is by mathematics, the simple axioms and mathematics appeal to him. I mean, if I say that table is solid, all sorts of questions about that. What do I mean by solid? Will it be solid under the micro? So it's clear in that the idea is in front of you, but it's not distinct because it's not, it doesn't consist only in clarity. It's got all of this other fuzzy stuff as well.

What do these words mean? Does the external world exist? What is wood? Are atoms mostly empty, you know, all of this kind of nonsense floating around? Sure. Whereas two plus three equals five, there it is on its own. There it stands. Now, it implies nothing except what is present.

And this really leads on to physics for Descartes, because he thinks, rather like Galileo, his near contemporary, that mathematics is the key to science. This was something revolutionary and new in the 17th century, which has proved to be substantially correct. Descartes had these mathematical laws of physics, which were all wrong. Newton, a few decades later, much better ones. They're both agreed on the mathematical principles, which for Descartes are, in their simplest form, are guaranteed by the benevolence of God. So here's something really important then, right? So Descartes has established, through the light of pure reason, clearly and distinctly, that God exists, because the idea of God as a perfect being and therefore a trademark within us is clear and distinct, and therefore I know that God exists. And because God exists, I know that I can trust my clear and distinct perceptions. But if you need to believe in God to trust your clear and distinct perceptions, but Descartes has proved the existence of God as a clear and distinct perception,

isn't he arguing in a circle? This is what's known as the Cartesian circle. Yes. Yes, Cartesian from Carthesius, the Latin version of Descartes. Which is such a cooler version of his name, don't you think? Cartesius. Hattesio. I might start calling him that instead.

Well, in Italian, he's called Cartesio. So, yeah, whether the circle can ultimately be broken out of, I don't know. But I think it's so far as Descartes does it, it's by this idea of immediate focus, as long as I'm actually here and now focusing. So the certainty is very limited, very temporary. And actually you mentioned Pascal earlier, I think actually that comment is unfair to Descartes, although much of what Pascal says I think is fascinating. But in this point, Descartes doesn't make a distinction between creation and conservation.

That's to say, God recreates a new every second, every moment, every split second of time. And without that conserving power of God. God, things wouldn't exist at all. So I can know I exist as long as I'm thinking, but unless God conserves me from moment to moment, and the same with the whole cosmos, it would not exist. So the God Descartes discovers is very similar to Thomas Aquinas' God. Sustain, that's what I was just thinking.

Who is the sustainer as well as the creator. Yeah, quite, quite. Okay, so this problem of the Cartesian circle, to be clear, We talked about 2 and 3 equals 5, but if I'm not mistaken, when Descartes is considering all the things he can doubt, he starts, you know, with the external world, and then he thinks about maths. And as far as I'm aware, he does think to himself, the evil demon could even make me go wrong every time I add 2 and 3. This evil demon that exists, even with something as as obvious to me as 2 and 3 equals 5, it's possible that every time I do that calculation, the evil demon just prods my brain and me. makes me go wrong every single time. And so weirdly, before we've established the existence of God, Descartes thinks he can't even trust those most clear and distinct perceptions, but he then

establishes God's existence through a clear and distinct perception. So is this a functional criticism of Descartes? Is it something he addresses? He does, I think. And the answer he offers, I think depends really on, if you like, the difference between a first order and a second order of doubt. The doubts you've just raised up, oh, maybe I could go wrong about my simplest mathematical intuitions. But then the first order question is what I'm now focusing on when I say two plus three equals five, could I be wrong about that?

And Descartes's answer is no. As he puts it in the third meditation, when I... I've raised the doubt of the demon, but when I turn to the truths themselves, which I think I perceive so clearly, I'm so convinced that I declare, I'm quoting from memory, let him who will deceive me, he can never make it that I'm nothing as long as I think I'm something or that two and three are more or less. Which, by the way, out of context is a wonderfully motivational quote, isn't it? Like, let any demon try as hard as he can. He will never convinced me that I am nothing. I remember underlining that when I first came across

it thinking that would look good on a poster. But okay, so, and really important here is like the immediacy. Right. Descartes is not saying like, okay, with these, at least in this first stage, you know, here are these mathematical truths and here's, you know, my thinking and here's like, you know, God's perfection. And so, all right, that's all settled, put that on the shelf. I've proved that God exists. And for the rest of my life, I can say, oh, I know that God exists. And if someone asked me why, I go, oh, well, because of, oh, there's this proof. It's only when you've got it in your mind that you can have the certainty, only in that moment. And what Descartes wants to do is transition from the certainty he can hold in the

moment of clearly and distinctly perceiving God's existence. Right there and then, I know that God exists. But now, five seconds later, I remember that I thought God exists, but I can't be certain of it until it's actually in the brain. But Descartes wants to move from that immediacy. to a more broad epistemology. And he does that through, well, that the knowledge of God is immediate, which establishes the trustworthiness of my clear and distinct perceptions,

and so then I can take God out of my mind and now trust my clear and distinct perceptions. It's as if this tiny flicker of this candle of certainty, my own existence, and then I can reach to God's existence, And then the candle is, as well, lit the bonfire. And now the whole room is illuminated. Right.

And you need that candle to light the building. And the candle needs to be there and then, like, while you're holding it. But once you've lit the room, then the candle can go out. And if we sort of relate this to our modern ideas, I think we do have an idea of the world as it really is, the truth as it really is. Bernard Williams described this as the absolute conception, you know, the conception of the cosmos as it would be agreed on by any rational inhabitant of the galaxy or the cosmos, something objectively and absolutely true. The question he raised is, because he strongly criticized Descartes's proofs, whether we can get there without God, whether without this metaphysical bridge we can

reach absolute conception of truth. And it's doubtful. It's doubtful that we can. In other words, if we delete the whole idea of the reliability of the mind, the God-given reliability of the human mind in its most basic logical and mathematical intuitions, then do we have any principled hope that we are creatures who might be able to reach the truth. So the whole enterprise of philosophy and of science is then not exactly thrown into doubt, but there are worries there about why we should think that this randomly evolved creature, Homo sapiens,

should somehow be equipped to discover authentic, objective truths about the universe. Yeah, and that's why I think it's also important to distinguish between. I mean, one of my criticisms of Descartes has always been, and not to say that I disagree with him, but the criticism that comes to mind that may or may not have an answer, is to say that, of course, conceptually, if I'm certain of something, then I think it's true.

And it's impossible to know something unless it's true. But in this epistemological project of trying to doubt everything that's possible, I think that all Descartes is really establishing here is what he cannot doubt. What are the things which it's impossible for a person to doubt? If it's impossible to doubt it, obviously we're going to think that thing is true, but I'm not sure that Descartes has established truth. I think he's established what it's impossible to doubt, what you can be certain of, which, as I said earlier, I don't think is quite the same thing.

I don't know if Descartes reflected heavily on this distinction, whether he thought he was doing one or the other. And I don't know if you have a view on that, but I think it's an important undertone. It is. And the distinction your drawing is very important because we don't want science knowledge to be based just on a psychological fact.

Exactly, yeah. That we are strongly inclined to believe X. Yeah. We want, I think Descartes does offer an answer. namely that when I am convinced, spontaneously convinced of the truth of, let's say, two by three equals five, it's not that my feeling makes it true or makes it certain. It's rather the nature of the thing itself, as he puts it. Because in a way, the certainty that Descartes has established is not just exactly a certainty that two plus three is five,

but if you like, the certainty that that is true. And so he has sort of established a certainty in truth. Yes. And, I mean, I think we'd say that it's the nature of the mathematical properties themselves that means that two and two have got to make four. Yes. So, and this very much connects with his later proof of God's existence in the fifth meditation when he says that it's not my wanting,

it to be the case, when, for example, I say the angles of a triangle equal 180. Yes. It's not that I make it so or that I dream it up. Rather, it's when I contemplate this triangle, I say, yes, it's got to be the nature of the triangle itself. Yeah. Essence, how the triangle is defined means this property has got to follow. Similarly, he says, it's not that I'm putting existence into God, rather the very nature of the essence of God how he's defined if you like means that his perfection so got to include the perfection of existence

yeah crucially and this I will talk about this the dreaded ontological argument in Cartesian form crucial I'm glad we're doing this first rather than afterwards is to point out that there is there is a really important difference between like an epistemic tool and like metaphysics the truth of the matter right it may be the case that way the way we're

certainty is through a mental exercise. We might think P is certainly true because I've used some mental exercise that establishes the truth of P. That does not mean that P is true because I think it's true, right? That's not the same thing. So, crucially, I mean, if you think about a triangle and you think about the fact that it's got three sides, right? If you reflect on that in your mind, yeah, that's true. Triangles have three sides. Why is that? You think, it just does. Or those angles add up to 180 degrees if you don't like the definition problem of triangles. It just does. And it's not that I've invented that in a way that I'm sort of arrested by the truth of it when I reflect on it.

You know, the same thing, why can't something be true and false at the same time? Laws of logic. They just can't be. Why not? Because when I reflect on it, I'm just arrested by its truth. That doesn't mean that I have thought the law of logic into existence. it just means the way that I've established my certainty in it is through my inability to think of the opposite, right?

So with that caveat, and I just want to really stress for our listeners, you know, to say that like my inability to conceive of something means it's impossible does not mean it's impossible because I can't conceive of it. It means that I can't conceive of it because it's impossible. That in mind, Descartes' ontological argument, Why does he revisit the question of God in Chapman in Meditation 5? It's an interesting question why he thinks he needs a second proof. Yeah, the first one is done the job.

But I think the point is at this stage, he's entitled to be sure, he thinks, that he will have the kind of knowledge that's founded on clear and distinct perceptions. So it's going to be the kind of knowledge we see in mathematics, his favoured model for knowledge, whereas we were just saying in the case of 2 plus 6, 5, the nature of the thing itself is so clear that it forces my assent, really. And so he's now going to produce a proof of God that has that same quality. As he puts it in the fourth meditation, from a great light in the intellect, there follows a great propensity of the will. And when I see something, a mathematical theorem so clearly, I just got to say, yes, it's true. Yes.

Because the clarity attaches to the thing itself, not to my subjective inability to doubt. Now, in the case of God, he's reasoning, God is defined as the sum of all perfections. Existence is a perfection, therefore God exists. So you can no more prize existence off the concept of God. then you can prize angles equal 180 away from the concept of the triangle. Well, personally, I think, well, not just personally, but few people I think have been wholly convinced. Thomas Aquinas in the 13th century rejected the ontological argument, and I think he got it

right. Roughly, he's saying, yes, existence, you can define God. as that than which nothing greater can be conceived. That was Anselm's definition in his version, earlier version of the ontological argument. And existence will seem to follow from that. But all you've shown is that existence is linked to that concept of that than which nothing greater can be conceived perfection. You haven't shown that anything actually qualifies for that title.

in the first place. And I think as far as my own view is concerned, that criticism is ultimately right. Yeah, well, my listeners will know that I place a lot of stock in the ontological argument. I think it's great fun,

and I think it's got a lot, at the very least, it's got more plausibility than people give it credit for, but I never talk about Descartes version because I find it to be the weakest. I mean, you just said that, you know, God is defined by Descartes as the son, of all perfections. People will immediately say, that might not be a great definition of God.

But okay, back to what we said earlier, forget the word God. Let's just prove that there exists this being, who is the sum of all perfections. And call it God if you like, up to you. Okay, so what is a perfection? I guess one way we could define it would be like, you know, doesn't have any limitation, you know, so unlimited in knowledge, unlimited in power, unlimited in love. And Descartes wants to say, therefore, also unlimited in existence. And importantly for Descartes, like, there are levels of existence, and for the scholastics before him who would have dominated the schooling that he had, you know, for Aristotle,

the redness of a telephone box exists, and the telephone box also exists. But the redness has, like, less existence because it relies on the telephone box, whereas the telephone box has existence in itself. So there are, like, degrees of existence. So for Descartes, we're just imagining this being of all perfections, which is to say no limits. So no limit in power, no limit in love, and no limit in existence, which means he exists. And that means that if you're imagining this being, which everyone at home should be doing by now, you're just picturing this being in your head, well, you're picturing a being that has maximal existence, which means that that being exists. So you've just established the existence of God.

And the first thing people always say is you can't just think God into existence. Yeah, you can't just have a thought and therefore God exists. But remember what we said a moment ago. It's not that my thinking makes God exist. It's that the sort of clarity of the thought establishes the truth which arrests me when I reflect on it. And the truth that a being which exists exists arrests me. when I think of a god who, a perfect being who must possess existence. Indeed, I think that's a very fair way of putting what Descartes himself would say.

He actually says in the fifth meditation, my thought imposes no necessity on things. Exactly. Rather, it's the nature of the thing itself that means that whenever I focus on this concept of supreme perfection, I am obliged to acknowledge that existence must be part of that. Well, it may be an inseparable part of it, but we also want to know, I think this is what the critic's going to say, whether in actuality there is any being who qualifies for this title. Once you grant him the title, then he'd have to exist, put it crudely.

but there may be nothing that so qualifies. And of course, I mean, it makes sense to think, it almost feels like a bit of a trick, but I think people say the ontological argument is sort of circular, just defining God. And in a way, the advocate wants to say, well, yeah, because all deductive syllogisms are, in a sense, circular, they're tautological. And all we're really doing is reflecting on the nature of God. And by definition, he exists. So, yeah, in a way, we are just defining God into existence. And so it sort of seems a little bit plausible, but then people start thinking, okay, well, then

can't I just define all kinds of objects? So let me just conceive of, you know, the unicorn which exists. Everybody just imagine the concept of the unicorn which exists. Well, if you're imagining the concept of the unicorn which exists, then it must exist. So this unicorn you're imagining must exist, right? This is an important criticism of Descartes's ontological argument. How might Descartes respond to that? That, I think, is a matter of distinguishing between concepts which you just cobble together.

I've got the existing unicorn, or even the unicorn, actually, horse plus, or I can cobble them together, but then I can take them apart again. Whereas in the case of the triangle, which is a genuine geometrical entity, and ends Verum, as Descartes puts as a true entity, not meaning it exists, but just. it's a it's a true mathematical object um i can't i can't decide for myself what to add and what to subtract yeah again as you were saying earlier the nature of the thing itself requires me to draw certain the 180 degrees of a triangle is not something that you can just you know add to it oh let's make it 190 you can't do that it's it's you're forced into doing it with a unicorn i can say the unicorn that's blue, the unicorn that's got three legs, the unicorn that exists. I'm just making stuff up.

It's not like forced by the concept, right? And I think importantly here, we also need to distinguish between something's essence and something's existence. I'll try to do this as briefly as possible, but like, as far as I understand it, you know, something's essence is what makes it what it is. So say this chair, for example, you know, what makes this a chair? Well, the fact that it holds things up, the fact that it's, got legs, the fact that, you know, all of this kind of stuff. Once I've established the essence

of the chair, I can then separately consider the question, does it exist? Same with the unicorn. The unicorn has an essence, and whether or not it exists, the essence of the unicorn doesn't change. It can be added or subtracted to the essence. Exactly. Whereas in the case of God alone, this is the exception, in the case of this supreme perfection alone, according to Descartes. You don't have the choice of whether to add or subtract existence. It's got to be there. And of course, Aquinas in the 13th century had defined God as Ipsum essay, existence itself. So there is something there, I think, which is perhaps retains an appeal, this idea of pure actuality. There is, it's indefinable, almost incomprehensible notion.

actually being here, actually existing. I think it's not a bad defense to say, like, you know, say this table or this book or the unicorn, all of these things are things which have essences, you know, they have things which make them a table, even the thing that doesn't exist, like the unicorn, or the imaginary table, a different table that we're imagining. It has an essence. It's got legs. It holds things up in the mind, you know.

And adding existence to it doesn't change its essence. Whereas this conceptual being that we're being asked to imagine by Descart, the sum of all perfections, because it has existence as part of its essence, it's not the kind of thing that you can say, I'm imagining the essence of this perfect being, and then there's an open question whether it exists or not, because its existence is part of its essence. Whereas I can imagine the table or the unicorn or anything else at all, and then I can ask whether or not it exists. This is the one thing that you can't do that for because its existence is part of its essence. And in fact, for many people, a good definition of God is he or that which has existence as part of or as its essence. That's kind of what God is for people like that. That's what I was suggesting really, with the Thomistic definition of existence itself. Yes, I think that it's nice to find someone who finds something to be said for the ontological argument.

because it's not found many adherents. But there is something about the thought, I think, that once you have a concept of God, you're dealing with something that couldn't just happen to be around. It might not. Once you've reached the concept of God, you've reached something that is the source of all reality, yeah source of all existence source of all goodness and therefore as it were by its I think this is the essence argument by its very nature it's not something which happens to be here yes and you also consider the context in which this argument comes up as we said this is meditation five

Descartes has already in meditation three established god's existence through what to me although obviously it's an argument with its problems is a lot less of a sort of you're playing a little trick on us oh it's a circular word game it's an argument that stands or fails. And so in a way, I could say, look, Descartes already established God's existence. He already knows God exists. So now, by the time it's Meditation 5, yeah, he is just reflecting on the definition and arguing in a circle, but like, what's the problem? He knows he exists. So now he's just sort of reflecting on God's nature. In the same way that Anselm's original ontological argument, in scare quotes, comes from his prologian, which was not a work of philosophy. It's a prayer. Anselm is just reflecting on God's nature,

and that's where these ontological arguments come up. That's true. I mean, that's more apparent, I think, at Anselm than it is in Descartes. I think so, too. As you rightly say, Anselm begins by expressing his puniness,

his humility before this greatness of God, and asks from a position of faith, he seeks understanding. Yes. Whereas Descartes is the definition of starting with ego. Right, yes. Although, yeah, although he did say that although in the order of discovery, he comes first,

in the order of reality, God comes first. So I don't think he's quite turning the tables on the future. It's a beautiful way of putting it. And where is it that Descartes, you quoted earlier, Descartes saying, let's just pause for a moment to reflect on the range of course. Yeah, that's the final paragraph of the third meditation. Yeah. So at that point, he's already thinking in terms of, like, maybe we just need to take a moment to just reflect on the majesty of us. I think he's almost in Anselmian mode, actually.

Yeah, yeah, yeah. And I just wonder, even if it's not entirely clear, or maybe even if you wasn't doing this quite unpurposed, I wondered the extent to which that might be present in Meditation 5 as well, wherein, I mean, I can't remember the syntax, I can't remember how it's put forward, but for a lot of people, the reason why they don't like the ontological argument is because I like, I'm not convinced by that. But as Plantinga says, of his modal ontological argument, it's not for you. It's not for people who don't believe in God to convince you. It's for people who do believe in God to justify that belief. Yes. I think there's elements of that in Descartes, but I think he also wanted to say that

he was doing the kind of philosophy that would carry conviction anywhere irrespective of whether you're a believer or not. And certainly would, as he put it in the interview with Berman would appeal to anyone, even the Turks. That's to say those who weren't in the Christian tradition. Yeah. Okay. So we've done a bit of a tour de force of the meditations. I mean, we've been talking about Descartes more broadly, but we've roughly gone through the sort of meditations. The first is the skeptical method. The second is the cogito. The third is the trademark argument. What's the fourth? The fourth is about the relation between the intellect and the will, which I think connects with what we are talking about,

the ideas of a great light in the intellect leads to spontaneous assent of the will. Then we get number five, which is this ontological argument as well as material existence. There's one more meditation in this text, the sixth, which is about the mind and the body. and the body. Descartes is probably second most famous for his so-called Cartesian dualism, this mind-body distinction. I wonder if, since we're doing an intro to Descartes, whether it might be worth just touching on that before we round up.

Yes. Well, we've left to the end what's possibly the part of Descartes's philosophy that attracts the most attention nowadays. He's a dualist, that's to say he divides reality into two fundamental categories, raise cogitans, thinking stuff, and raise extensar, whatever can be measured or quantified, whatever has length, breadth, and height. The second category is the basis of his whole of physics, his mathematical physics. So it's a world of measurable particles whose size, shape, motion, speed you can assess. That's the world of physics. I think we still have that conception. And then we have

the world of conscious thought, which for Descartes consists of intellect and will in the way we've been discussing in connection with the cogitin. And so what's the relation between those two very distinct things? Descartes is a dualist. That's to say he thinks these are two really incompatible notions. You can quantify any physical object, the table, the chair, atoms, particles. You can't quantify the mind. You can't measure it. But his view that the mind is an immaterial substance is one which I think it's hard for us to accept these days, because we seem to be so clearly aware that what's doing the thinking is a human being possessed of a very complex nervous system and brain, a brain consisting of millions and

millions of neural connections. So the idea that thought could be the property of an immaterial substance or soul is, I think, lost a lot of its appeal for us. But since we've got on to Descartes' dualism, let me just add a point which I think is not sufficiently adverted to by those who study they can't now, namely that although he says that mind and the body are two distinct things, he also, in the sixth meditation, says that they're united. And when they are united, very interesting things happen. We have emergent properties, namely feelings, emotions, sensations, which are not really pure thoughts. They're not pure cogitations, but nor are they mere physical, physiological reactions. They somehow straddle that category. And so my view on this

is that although Descartes has only two substances, mind and body, he has three kinds of attribute or qualities. Purely mental attributes, like thinking and willing, purely physical attributes like your stomach rumbling or your blood pressure or whatever. But then there's this third category of attributes, thoughts and feelings, passions, which are psychophysical. They involve conscious awareness, but they also involve physical stuff, as we say, being churned up about something. Yeah, yeah. Which is an interesting phrase because it implies it's not just a pure abstract thought. There's a bodily component too, which has a particular kind of urgency. Am I right in thinking that Descartes connected

the mind to the pineal gland in the brain? Is that like an urban legend? Is that something that he really did? No, he did. That's what Daniel Dennett, the American philosopher just died recently, called the fax machine to the soul. It's where all the physical neural impulses come. And then in the pineal gland in the middle of the brain, they somehow perceived or transmitted to the... How did Descartes? I mean, how much did Descartes know about the science of the brain, as we would consider it today? It's very crude by today's standards. He thought of the nerves of little pipes filled with gas, which he called the animal spirits.

So he had no conception of the staggering. He was very interested in physiology. and in the nervous system, but no real conception, the staggering complexity of the cerebral cortex. But he had some idea of how the brain worked

to the extent that he knew that this pineal gland was, he sort of knew roughly what its function was in the brain. I mean, I really don't know where the science of the brain was at that point.

I think it's pretty crude. He just wants a single point where the images from the two eyes come together. Right, right. I think it doesn't really cut much eyes with us now. What I think is

is an interesting argument is that he says that a mechanism, a physical mechanism, always has a finite number of inputs and outputs. But thought, he says, is open-ended. It's not based on one-one correlations, input, output, input, output. Today, you've uttered sentences you've never uttered before. You've had thoughts which you've never had before in exactly that form. So the mind is creative, innovative, and he thought, therefore, it can't be reduced by a physical organ, however complicated. And actually he has a sort of empirical argument for that. He says, you just couldn't fit in enough mechanisms into that space. But of course, it's an interesting question, had he known that there were hundreds of millions of neural...

Yeah, would he have thought that that was enough? And would he still had this argument? But I think he comes out as in pretty good shape, I think, by today's standards, because that's still quite a compelling argument for the creativity of the mind, and how physical mechanisms don't seem to have that capacity. Yeah. Okay, so then two questions to round up this mind-body stuff. first, we've just talked at length

about Descartes believing that there's a mind that's separate from a body but we didn't talk about why he believes that. I mean, in the sixth meditation he gives a relatively straightforward again sort of remember we're on the skeptical journey of things that we can doubt like what does our reason reveal to us?

Why does Descartes land on this idea that the mind and the body are distinct things? The basic argument which occurs in the discourse on the method written a few years before the meditation is that, to put it crudely, I can think of myself without the body. I can conceive of myself waking up without my body in the next world, perhaps.

I can conceive, I can imagine, or think at least it's logically possible that I could still be me, this thinking being, even though there was no body. Some people still buy that argument, Richard Swinburne, who I think you've interviewed on your program, thinks it's a good argument and has a very sophisticated modern version of it. My view is that it doesn't work. The fact that I think I can conceive of myself without my body existing doesn't, I think, prove that I could really continue to be me and to think and to discuss and to meditate without my body,

which would include without my brain. Um, after all, we often make mistakes about what could happen without what. I could perhaps imagine or think I can imagine this water without there being any hydrogen and oxygen. Quite right, yeah. But unbeknownst to me, if I'm ignorant of chemistry, it just can't be there without the hydrogen and the oxygen. That's what it is. Yeah. You can imagine, I mean, you can imagine somebody who, like, didn't know that water was made of hydrogen and oxygen.

Even like outside of the context of water itself, thinking to themselves, for some reason they were like, imagine a possible world in which the only thing that existed was, you know, the ocean, but there was no hydrogen, you know, and they didn't even realize that those questions were connected. You can conceive of that. You can conceive of there being, oh, no hydrogen atoms at the center of stars and stuff, but there's just a bunch of water. But without realizing it, you have undermined the thing. I mean, I think the argument's powerful. And it's worth pointing out to people as well that, like, Descartes isn't, isn't. trying to say that, like, the mind is distinct from the body because, like, and sort of imagining them as being distinct. I just know that they're distinct. The point is that as long

as you can conceive of them being separable, that means that in principle they are separable. It's at least, yes, it's at least logically possible that they were, they're separable. And so that, and just that conceivability means that they can't, literally speaking, they can't be the same thing. Because if they were the same thing, you wouldn't be able to conceptually distinct them. Even if in practice, they always come together. the conceptual distinctness is what makes Descartes think that they are actually distinct. Yes, but I would add that it's still an open question whether that conceivability is genuine, as to say whether my conception is coherent, whether I can coherently conceive.

I just add one thing that there is some appeal, I think, to the idea that thought is abstract. Yeah. We're now discussing pretty abstract questions, which don't appear to be connected with matter. Nonetheless, what is doing the thinking could still be a physical, namely an animal, a rational animal, a human being. So although there's something to the thought that thought is an abstract process, the idea that the individual who's doing the thinking is an immaterial soul. I think it's, in my view, is not proved. Yeah.

There are some important questions in that idea of like abstracting ideas, for example. I can conceive of the brownness of this chair as separable from the chair. Like I can separate those concepts in my mind. But does that mean that the brownness could sort of exist on its own? Right. Well, I want to say no. But then maybe kind of because it like exists in my mind and it all gets a bit complicated. But at the very least, I think it's fair to say that even if it is the case that if something is conceptually distinguishable, then it is really distinct.

The problem is that we often just go wrong with what we think is conceptually distinguishable. Absolutely. And that's even granting that that is the case. It may also be the case that conceptual distinction doesn't guarantee real distinction. Yeah, so that all sorts of problems, I think, with Descartes' central argument for dualism. And as I say, I think it's a view that's kind of lost its appeal for us today. And my own view would be that Aristotle got it right, that the attribute of thought may be a separate kind of attribute,

but it's an attribute that inheres in a human being. And a human being is a creature of flesh and blood. It's a living organism, which has many properties, in virtue of the way the body is configured. So I can digest in virtue of the way my stomach is configured. I can think in virtue of the way my brain is configured. That's what's known as the hyalomorphic view, which Descartes thought he was rejecting,

and indeed he did reject it. But arguably, the Aristotelian view is the common sense view. If you say, what are you? I think it'd be very odd to say I'm a soul it'd be equally odd to say I'm a body I think the right answer is neither I'm not a soul as Descartes thought

I'm not a body as sort of reductionist materialists think rather I'm a human being a creature of flesh and bud a biological animal of a certain rather unusual kind because we have the power of thought but that's a power that's located

in or inheres in the biological being that's a human being. Yeah, it's parts of a whole. I'm not my left side, I'm not my right side, I have to be both of them together. The only question that jumps out of that from me is another really important legacy of Descartes which I think is worth an honourable mention at the end here which is a few times there you said human being,

rational animal, we are people. Descartes didn't extend this sort of charitable view of insolment far beyond the human beings. human species. Famously, Descartes, if I'm not, again, this might be an urban legend here, but I have a feeling that Descartes once attempted to prove the sort of, I guess, inanimate, not inanimate, but the soullessness of animals, other animals and humans by like cutting open a dog.

And I'm not sure if that actually happened or if that's an urban, urban myth. He did, he did do vivisection on rabbits and dogs. his view of animals, I think, is not as clear as is often supposed. He describes them as automata machines, but an automaton in the 17th century just meant a self-moving mechanism. Now, what he denies clearly and unequivocally denies of animals is thought, the power of thinking, cogitating, meditating, conceptual thought.

And that seems to me is absolutely right. Animals don't have language, they don't have thought. As to whether they have feelings, he does talk about animal passions. He does, you, says, for example,

that when a sheep sees a wolf and runs away, it has the passion of fear. He talks about passion of anger as applying to some animals. So he's not on the face of it denying the possibility of genuine ascriptions of feelings to animals. And importantly, animal pain.

Yes, indeed. He thinks that's explicable in terms of physiology, but to explain something in terms of physiological mechanisms is not to eliminate it. So I think Descartes's position, actually, perhaps we can end on this note, is rather more subtle and interesting than the crude denier of animals. feelings to animals that he's often represented as being. As is so often the case in the history of philosophy, it's more complicated than it seems at first glance,

and I'm so glad that this podcast gives us an opportunity to start unpacking things like that. John Coddingham, this has been a wonderful, wonderful introduction to Descartes. I've learnt, even having thoroughly studied your works during my university degree and afterwards,

I've still learnt dozens of new things just from sitting talking to you now so thank you so much for the time thank you very much enjoyed it and and thank you for your very interesting and apt questions which i hope have produced some interesting thoughts for our for our viewers we'll see what they think like and subscribe let us know in the comments